Stadia-rod



E. H. SCHWIER.

STADlA ROD.

APPLlCATlON FILED JAN. 21.1920.

1,381 ,023. PatentedJune 7,1921.

i/V VEN TOR A TTORNEYS EMMETT H. SCHW/El? UNITED STATE EINLMETT H.SCHWIEB, OF HUNTINGTON, NEW YORK.

STADIA-ROD.

Specification of Letters Patent.

Application filed January 21, 1920. Serial No. 353,126.

T 0 all whom it may concern Be it known that I, EMMETT H. Sorrwnsn,

a citizen of the United States, and a resident of Huntington, county ofSuffolk, and State of New York, have invented a new and improvedStadia-Rod, of which the following is a full, clear, and exactdescription.

This invention relates to surveying lnstruments, and has reference moreparticularly to a stadia rod provided with graduations consisting ofunit measuring figures on sald rod, each of which is placed at an angleto the axis of said rod.

An object of this invention is to prov de a form of graduation for astadia rod which will be simple and free from complicatlons andrefinements tending to confuse or delay the transit man.

Another object of this invention is to provide a form of graduations ofthe class described which will be perfectly plain and legible on longsights with a transit and capable of precise readings on short sightsWithout the necessity of interpolating or estimating the smallerintervals.

I am aware that a number of forms of graduations are now in general usewhich satisfy any two of the above requirements, but none can fulfil allthree conditions, particularly those with reference to precision onshort sights, and legibility on long sights.

Reference is to be had to the accompanying drawing forming a part ofthis specification, in which it is understood that the drawing is merelyillustrative of two examples of the invention, and in which Figure l isan elevation of a stadia or leveling rod showing the disposition on therod of my improved graduated figures.

Fig. 2 is an elevation on a large scale of one form of one graduatedfigure, which for convenience is considered equal to one foot on thestadia rod.

Fig. 8 is an elevation on a large scale of a second form of a graduatedfigure, also taken as equal to one foot on the stadia rod.

Fig. 1 is a modification of the design particularly adapted to levelingrods.

Referring to the accompanying drawing by numerals, 10 indicates a stadiarod of any suitable material such as wood, metal, etc, and of any lengthwhich is convenient to use. The divisions or graduations of said rodsare formed by figures 11, and 12 said figures having alternate differentdepths of color so as to be easily differentiated through the telescopeof a transit. The major axis of each of these figures, or the longestline which can be drawn through each of the figures, is inclinedslightly at an angle to the longitudinal axis of said stadia rod, asshown clearly in Fig. 1, so that the bottom line of one figure does notregister with the top line of the adjacent figure, thus making the unitfigures independent and distinct at a long distance. As stated, eachfigure is assumed to represent one foot in length on the stadia rod, andtenths of a foot are in dicated by points 13 and 14:. The points 13extend in a direction opposite to the points 1% so that on long sightswith the telescope on the transit, the half feet will be fartherdifferentiated. In order to make the half foot divisions on the figuresmore striking, the points 13 and 14 extend on both sides of the figure10 at the half foot mark, so that the figure at that point appearsto bethickened on long sights. Each of the tenth divisions is numbered bynumerals 15, which will be plain and legible on short sights. In orderto divide the figures 11 and 12 into twentieths and one hundredths,reentra-nt angles are provided which form Patented June '7, 1921.

points 16 and 17, which extend in opposite directions into said figure,and a series of five steps 18 is provided on each side of said reentrantangles. These steps 18 divide each of the twentieths of a foot into onehundredths of a foot, and are plain and legible on short sights withoutthe necessity of interpolating or estimating the smaller intervals. Thenumerals 19 are placed on a stadia rod in heavy black script against thewhite back ground so as to indicate the foot divisions on long sights.The modification shown in Fig. 3 is adapted principally for closereadings on long sights on the transit, and is not provided with thesteps 18 which gives the instrument a high degree of pre- .ClSlOIl.

' In the modification shown in Fig. 4:, the points of each figure areturned in a single direction so that the figures will be in one verticalcolumn instead of oblique as shown in Fig. 1. This modification isespecially adapted for close work on levelin rods.

The advantages of my improve graduated stadia rod are many. Thealternate figures on the rod'are a thick black continuous outlinepainted on a white surface and will be plain and legible through thetelescope so far as one can see the rod, when smaller lines and figuresare not visible at by the double point so that said half foot point Willbe clearly visible Without interpolation or estimation. The even tenthsof the foot are points of emphasis, and are necessary for precise WOIl'Ion. short sights Where they can be seen, and the twentieth of a footmarks are indicated by notches. The step arrangement to indicate onehundredths of a foot is plain and unmistakable. At the same time itlends itself to the purposes of the broad general outline of thefigures.

special advantage is that by introducing a half step at theterininationsof the figures as shown in Fig. 2, the reading of atelescope "hair on any one step is made constant, that is when thetelescope hair crosses any part of the vertical face of the lower step,the reading of the rod is one one-hundredth and this reading will beconstant Whether the hair crosses this step at its highest or at itslowest point. While I have illustrated a foot as a unit, any othersuitable unit may he used such as the meter, etc.

Having thus described my invention, I claim as new and desire to secureby Letters Patent:

l. A stadia-rod having graduations consisting of a plurality of unitfigures Whose major axes are inclined atan' angle to the longitudinalaxis of said rod..

2. A stadia-rod having'graduations consisting of a plurality of unitfigures Whose major axes are inclinediat an angle to the longitudinal.axis of said rod, each figure having a plurality of reentrant anglesadapted to divide it into fractional parts of a unit.

3. A. stadia-rod having graduations consisting of a plurality ofindependent unit figures whose major axes are inclined at an angle tothe longitudinal axis of said rod, each figure having a plurality ofreentrant angles adapted to divide it into fractional parts or a unit,and a plu ality of steps sociated with said angles adapted to furthersub-divide said fractional parts.

EMMETT H. 'S GHWIER.

